The nuclear plant is clearly the best (even though there is a risc)
But you forget one thing.. The Manufactoring Plant is not a replacement for another plant, but an addition.
This means you can have a Factory, a Nuclear Plant and a Manufactoring Plant all in one city..
Correct me if I'm wrong, but I think this gives the following example:
MyCity has 30 shields without improvements (base-production)
Factory gives a +15 shield bonus to the base-production.
Manufacturing plant. gives a +15 shield bonus to the base-production.
Nuclear Plant gives a +150% bonus to the factory's output. Thats 150% of 15 shields = +45 shields.
Base : 30 shields
Factory : + 15 shields. Total 45 shields.
Manufacturing plant : + 15 shields. Total 60 shields.
Nuclear plant : + 45 shields. Total 105 shields.
If you are lucky, you can have the Iron works aswell. I'm not quite sure if the Iron Works doubles your base-production., or the total production including all bonuses.
In any case, the Iron works should then give you a production of eighter 135 or 210 shields.. kickass
